Within the sphere of the silicone water repellents used on fibers and fiber-based products, Japanese Published Patent Application Sho 51-9440 (9,440/1976) and Sho 53-4158 (4,158/1978) teach water repellent siliconee compositions with an aromatic or aliphatic hydrocarbon solvent and a curing catalyst. One of the drawbacks of these silicone water repellents is they must be cured at high temperatures before they are effective. The curing process increases production costs and does not allow consumers to apply the silicone water repellents to products of their choosing.
In other protective coatings, fluoropolymers are employed for their ability to impart water repellency and stain resistance to solids. These fluoropolymers are the polymers of a perfluoro group-functional or fluoroalkyl-functional polymerizable monomer or the copolymer of such a monomer with another polymerizable monomer. One of the problems with fluoropolymers is that they are insoluble in low-toxicity alcohols such as ethanol, and the organic solvent used to dissolve the fluoropolymers must therefore be selected from among solvents such as ketones, e.g., acetone or methyl ethyl ketone, esters such as ethyl acetate, aliphatic hydrocarbons such as n-hexane and n-heptane, aromatic hydrocarbons such as toluene and xylene, and chlorinated hydrocarbons such as 1,1,1-trichloroethane and trichloroethylene.
Unfortunately, almost of these solvents are not compatible with propellant gases or they are not readily absorbed into the solid surface being treated. In practice, only 1,1,1-trichloroethane is commonly used as a solvent for fluoropolymers in surface protectant compositions. The use of 1,1,1-trichloroethane is closely regulated because of environmental concerns regarding its potentially harmful impact on the ozone layer. Although researchers are trying to find other suitable solvents for flurorpolymers, which would be environmentally friendly, no viable alternatives are presently available.
Furthermore, when treating a solid such as a fiber-based product, leather, or other soft surfaces to impart water repellency thereto, the consuming public desires spray formulations to facilitate the application process and that are both easy to use and safe both to consumers and the environment. In addition, consumers also want spray-formulated water repellents that do not have an unpleasant odor is caused by high levels of solvents. Therefore, the use of high levels of volatile organic compound (VOC) solvents, commonly found in silicone-based protectants, is undesirable for both consumer and environmental safety.
There exists a strong consumer need for an aqueous, silicone-based protectant compositions with low levels of solvent or VOC exempt solvents which are effective in protecting surfaces from stains and soils and can be applied to surfaces by consumers.